Auto merge of #23532 - est31:unused_code_removal_4, r=emilio

Remove unused code (4/4)

<!-- Please describe your changes on the following line: -->

Fourth and final PR in a series of PRs to remove unused/dead code from servo, powered by an (upcoming) tool of mine. Please take a look and tell me if you want to keep something.

* First PR: #23477
* Second PR: #23498
* Third PR: #23499

Shortstat of the combined PR series:
```
47 files changed, 7 insertions(+), 805 deletions(-)
```

---
<!-- Thank you for contributing to Servo! Please replace each `[ ]` by `[X]` when the step is complete, and replace `___` with appropriate data: -->
- [x] `./mach build -d` does not report any errors
- [x] `./mach test-tidy` does not report any errors

<!-- Either: -->
- [ ] There are tests for these changes OR
- [x] These changes do not require tests because they only remove dead code

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components/style/animation.rs

@@ -181,14 +181,6 @@ impl KeyframesAnimationState {
         self.current_direction = old_direction;
         self.started_at = new_started_at;
     }
-
-    #[inline]
-    fn is_paused(&self) -> bool {
-        match self.running_state {
-            KeyframesRunningState::Paused(..) => true,
-            KeyframesRunningState::Running => false,
-        }
-    }
 }
 
 impl fmt::Debug for KeyframesAnimationState {
@@ -245,15 +237,6 @@ impl Animation {
         }
     }
 
-    /// Whether this animation is paused. A transition can never be paused.
-    #[inline]
-    pub fn is_paused(&self) -> bool {
-        match *self {
-            Animation::Transition(..) => false,
-            Animation::Keyframes(_, _, _, ref state) => state.is_paused(),
-        }
-    }
-
     /// Whether this animation is a transition.
     #[inline]
     pub fn is_transition(&self) -> bool {

components/style/attr.rs

@@ -298,18 +298,6 @@ impl AttrValue {
         }
     }
 
-    /// Assumes the `AttrValue` is a `Length` and returns its value
-    ///
-    /// ## Panics
-    ///
-    /// Panics if the `AttrValue` is not a `Length`
-    pub fn as_length(&self) -> Option<&Length> {
-        match *self {
-            AttrValue::Length(_, ref length) => length.as_ref(),
-            _ => panic!("Length not found"),
-        }
-    }
-
     /// Assumes the `AttrValue` is a `Dimension` and returns its value
     ///
     /// ## Panics

components/style/bloom.rs

@@ -194,11 +194,6 @@ impl<E: TElement> StyleBloom<E> {
         Some(popped_element)
     }
 
-    /// Returns true if the bloom filter is empty.
-    pub fn is_empty(&self) -> bool {
-        self.elements.is_empty()
-    }
-
     /// Returns the DOM depth of elements that can be correctly
     /// matched against the bloom filter (that is, the number of
     /// elements in our list).

components/style/data.rs

@@ -9,9 +9,7 @@ use crate::dom::TElement;
 use crate::invalidation::element::invalidator::InvalidationResult;
 use crate::invalidation::element::restyle_hints::RestyleHint;
 use crate::properties::ComputedValues;
-use crate::rule_tree::StrongRuleNode;
 use crate::selector_parser::{PseudoElement, RestyleDamage, EAGER_PSEUDO_COUNT};
-use crate::shared_lock::StylesheetGuards;
 use crate::style_resolver::{PrimaryStyle, ResolvedElementStyles, ResolvedStyle};
 #[cfg(feature = "gecko")]
 use malloc_size_of::MallocSizeOfOps;
@@ -373,29 +371,6 @@ impl ElementData {
         return RestyleKind::CascadeOnly;
     }
 
-    /// Return true if important rules are different.
-    /// We use this to make sure the cascade of off-main thread animations is correct.
-    /// Note: Ignore custom properties for now because we only support opacity and transform
-    ///       properties for animations running on compositor. Actually, we only care about opacity
-    ///       and transform for now, but it's fine to compare all properties and let the user
-    ///       the check which properties do they want.
-    ///       If it costs too much, get_properties_overriding_animations() should return a set
-    ///       containing only opacity and transform properties.
-    pub fn important_rules_are_different(
-        &self,
-        rules: &StrongRuleNode,
-        guards: &StylesheetGuards,
-    ) -> bool {
-        debug_assert!(self.has_styles());
-        let (important_rules, _custom) = self
-            .styles
-            .primary()
-            .rules()
-            .get_properties_overriding_animations(&guards);
-        let (other_important_rules, _custom) = rules.get_properties_overriding_animations(&guards);
-        important_rules != other_important_rules
-    }
-
     /// Drops any restyle state from the element.
     ///
     /// FIXME(bholley): The only caller of this should probably just assert that
@@ -413,11 +388,6 @@ impl ElementData {
         self.flags.remove(ElementDataFlags::WAS_RESTYLED);
     }
 
-    /// Returns whether this element is going to be reconstructed.
-    pub fn reconstructed_self(&self) -> bool {
-        self.damage.contains(RestyleDamage::reconstruct())
-    }
-
     /// Mark this element as restyled, which is useful to know whether we need
     /// to do a post-traversal.
     pub fn set_restyled(&mut self) {
@@ -438,13 +408,6 @@ impl ElementData {
             .insert(ElementDataFlags::TRAVERSED_WITHOUT_STYLING);
     }
 
-    /// Returns whether the element was traversed without computing any style for
-    /// it.
-    pub fn traversed_without_styling(&self) -> bool {
-        self.flags
-            .contains(ElementDataFlags::TRAVERSED_WITHOUT_STYLING)
-    }
-
     /// Returns whether this element has been part of a restyle.
     #[inline]
     pub fn contains_restyle_data(&self) -> bool {

components/style/invalidation/element/restyle_hints.rs

@@ -105,12 +105,6 @@ impl RestyleHint {
         Self::empty()
     }
 
-    /// Creates a new `RestyleHint` that indicates the element must be
-    /// recascaded.
-    pub fn recascade_self() -> Self {
-        RestyleHint::RECASCADE_SELF
-    }
-
     /// Returns a hint that contains all the replacement hints.
     pub fn replacements() -> Self {
         RestyleHint::RESTYLE_STYLE_ATTRIBUTE | Self::for_animations()

components/style/rule_tree/mod.rs

@@ -154,16 +154,6 @@ impl StyleSource {
         block.read_with(guard)
     }
 
-    /// Indicates if this StyleSource is a style rule.
-    pub fn is_rule(&self) -> bool {
-        self.0.is_first()
-    }
-
-    /// Indicates if this StyleSource is a PropertyDeclarationBlock.
-    pub fn is_declarations(&self) -> bool {
-        self.0.is_second()
-    }
-
     /// Returns the style rule if applicable, otherwise None.
     pub fn as_rule(&self) -> Option<ArcBorrow<Locked<StyleRule>>> {
         self.0.as_first()

components/style/sharing/mod.rs

@@ -102,15 +102,6 @@ mod checks;
 pub const SHARING_CACHE_SIZE: usize = 31;
 const SHARING_CACHE_BACKING_STORE_SIZE: usize = SHARING_CACHE_SIZE + 1;
 
-/// Controls whether the style sharing cache is used.
-#[derive(Clone, Copy, PartialEq)]
-pub enum StyleSharingBehavior {
-    /// Style sharing allowed.
-    Allow,
-    /// Style sharing disallowed.
-    Disallow,
-}
-
 /// Opaque pointer type to compare ComputedValues identities.
 #[derive(Clone, Debug, Eq, PartialEq)]
 pub struct OpaqueComputedValues(NonNull<()>);

components/style/stylesheets/import_rule.rs

@@ -21,6 +21,7 @@ use to_shmem::{SharedMemoryBuilder, ToShmem};
 
 /// With asynchronous stylesheet parsing, we can't synchronously create a
 /// GeckoStyleSheet. So we use this placeholder instead.
+#[cfg(feature = "gecko")]
 #[derive(Clone, Debug)]
 pub struct PendingSheet {
     origin: Origin,

components/style/values/specified/source_size_list.rs

@@ -54,11 +54,6 @@ impl SourceSizeList {
         }
     }
 
-    /// Set content of `value`, which can be used as fall-back during evaluate.
-    pub fn set_fallback_value(&mut self, width: Option<Length>) {
-        self.value = width;
-    }
-
     /// Evaluate this <source-size-list> to get the final viewport length.
     pub fn evaluate(&self, device: &Device, quirks_mode: QuirksMode) -> Au {
         let matching_source_size = self